Problems Morphing Floor to Topo

I am having issues transforming a floor to a topo.

All slabs thus far have worked great, however, the final portion shall not transform, forcing me to ‘reset shape’ of the floor.

I am having to use Dynamo 0.9.1.4062, and the office l am in currently will not update, therefore any assistance, much appreciated.

Could l use the mesh from the topo to create the floor itself?

Any pics?